Even though I think your earlier analysis of think is really good, wobbly, I also think that the viral site might be playing coy with us with respect to the sentinels. I think it is possible that they were around in the OT film timeline, but weren't active on US soil during the time of the movies. I made a (long) post about this issue here, but the concise version:

I find it suspicious that the production statistic doesn't go past 1996 -- it makes me wonder if the program was shut down (or regulated in a way that meant no new sentinels could be made) after that year. We also haven't seen any viral pics of sentinels that are clearly set post-1996 (as opposed to the Regan inauguration one). I think it's possible that sentinels were more active up until 1996 when the political atmosphere changed and they became more tightly regulated (perhaps unable to act on US soil) or even put out of service. Then after Magneto started stirring up stuff during the OT the US/World governments decided to use the sentinels on the mutants. (That would be when they started adding in the mutant detecting upgrades and designing the Mark X.)

Again, I don't disagree with your idea that we're looking at an already altered timeline -- I've defended that idea in the past. But I think, based on what we know/don't know so far, that it could go either way (altered or not altered) at this point.

Yeah, they could go either way. I do think that they will have to explain the Sentinels absence during the OT one way or another though (taken of service for some reason, or they didn't exist at all).

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